Arcturus returns to the morning sky – its helical rising. Morning Star Venus and Mars are visible before sunrise. Evening planets Mars, Jupiter and Saturn are visible after sunset.
by Jeffrey L. Hunt
Chicago, Illinois: Sunrise, 7:08 a.m. CDT; Sunset, 6:02 p.m. CDT. Check local sources for sunrise and sunset times in different locations.
Morning: Brilliant Morning Star Venus continues to shine from the eastern sky before sunrise. Now rising at 4 a.m. CDT, the sparkling planet is less than one-third of the way up in the east-southeast, 2 hours later. It is stepping through the stars of Leo. See our detailed chart for Venus in October here.
When Venus rises, Mars is the bright rusty-colored star that is about one-third of the way up in the west-southwest. It is retrograding – moving westward compared to the starry background – among the dim stars in Pisces.
The star Arcturus is now seen in both the morning sky – low in the east-northeast – about 45 minutes before sunrise. Use a binocular to see it. After sunset, it also appears in the west after sunset. The curve of the Big Dipper’s handle points to the star. In the morning the dipper is standing on its handle in the northeastern sky. In the evening the pattern is low in the northwest, possibly behind the neighbor’s house or the neighborhood trees.
This first morning appearance is known as the heliacal rising.
Detailed morning note: One hour before sunrise, Venus – over 22° in altitude in the east-southeast – is 0.8° to the lower right of Sigma Leonis (σ Leo). Mars is 5.0° up in the west. Try to find Arcturus low in the east-northeast, 45 minutes before sunrise. Can you see it without a binocular? This is the heliacal rising of Arcturus.
Evening: Mars, Jupiter, and Saturn are evening planets. Mars is visible low in the east as the sky darkens. As noted above, it is among the stars of Pisces. The planet is nearly in the sky all night long. Find it in the south as midnight approaches. Jupiter and Saturn are in the south after sunset. Jupiter is brighter than Saturn and nearly the same visual intensity as Mars. The giant planets are seen against the starry background of eastern Sagittarius. With a binocular, make observations each clear evening to note their changing positions compared to the stars. Jupiter is 6.1° to the lower right of dimmer Saturn. (See a chart here.)
As the sky darkens look for the crescent moon that is 3.2 days past the New moon phase and 14% illuminated. It is 4.9° to the upper right of Antares, the Heart of the Scorpion.
Detailed evening note: One hour after sunset, the Red Planet is nearly 13° in altitude above the east-southeast horizon. Saturn is nearly 27° up in the south and 6.1° to the upper left of bright Jupiter. In the starfield, Saturn is 1.8° to the lower left of 56 Sagittarii (56 Sgr). Jupiter is 3.5° to the lower left of Pi Sagittarii (π Sgr) and 0.9° to the lower right of Sagittarii (50 Sgr). (See a chart here.) The moon (3.2 days after the New moon phase, 14% illimunated) – over 10° in altitude in the southwest – is 4.9° to the upper right of Antares. Two hours after sunset, Mars is nearly 24° up in the east-southeast. It has nearly the same altitude as Saturn, now in the south-southwest. The Red Planet is 2.5° to the lower right of Zeta Piscium (ζ Psc) to the upper left of 89 Piscium (89 Psc), and 1.5° to the lower left of 80 Piscium (80 Psc).
Read more about the planets during October.
April 19, 2021: The first evening appearance of Venus for this apparition occurs this evening. Look for it low in the west-northwest about 20 minutes after sunset.
April 19, 2021: Venus begins to appear in the west after sunset. The moon lines up with Pollux and Castor, while Mars is above Bull’s horns in the western evening sky.
April 19, 2021: The bright morning planets, Jupiter and Saturn, are in the southeastern sky before sunrise. Capricornus is the starry background for this giant planet duo.
April 18, 2021: The crescent moon is high in the west after sunset among the stars of Gemini, below Pollux and Castor. Mars is above the Bull’s horns. Daylight is 13 hours, 30 minutes long.
April 18, 2021: The bright morning planets, Jupiter and Saturn, are in the southeastern sky before sunrise. Capricornus is the starry background for this giant planet duo. Daylight is 13 hours, 30 minutes long.